Alex Gamma <alex.gamma@uzh.ch> separately used the -atrisk- and
-risktable- options in two -sts graph- calls with data that contained
multiple records per subject. There was a large discrepancy in the
results from the two calls. The graphed -atrisk- numbers were
significantly larger than the -risktable- numbers. Alex compared with
-sts list- as well, and found these numbers matched the -risktable-
numbers. Some of the -atrisk- numbers actually exceeded the total
number of subjects in Alex's dataset.
Joerg Luedicke <joerg.luedicke@gmail.com> investigated the issue with
-atrisk- and -risktable- that Alex discovered. He also found that some
of the -atrisk- numbers exceeded the total number of subjects in the
data.
This is a bug in -sts graph, atrisk- that can arise in multiple record
survival data. We are investigating and will provide a solution in a
future ado update.
--Charles Lindsey
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